Service Upgrade 125 to 200 Amp Details

accord500November 8, 2010


As a homeowner, I have taken on lots of home improvement tasks, but the one that I have not found any good information about is a service upgrade. Does anyone have any good links to the basic requirements for upgrading the service?

I realize that this is no simple task, but other than reviewing the latest national electrical codes, I haven't found any good resources. I am hoping to piece together the information I have so that I can make a near perfect upgrade before the town inspector comes to take a look.

I am interested in anyone's knowledge, electrician or DIY homeowner.

I have many of the required materials supplied by my local electrical supply company, but even they are reluctant to give any detailed information about ground rod spacing, approved connectors for the ground rod, gauge of wire for grounding, method of attachment to panel, etc. These are just for the panel grounding.

Thanks in advance for the help. As I learn more I will post updates to this thread.

Some add'l info:

I live in NJ and this upgrade will also involve moving the service from a house mounted service to one that enters through a mast.

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As a suggestion, i would add a outdoor service disconnect (not required) and a square d qo panel. as long as you do not have a stab-lok panel you are okay, though. a disconnect will allow you to work in the panel with the panel dead as well as not making the firemen have to cut the se cable (they do in my area, anyway) in case of fire.

    Bookmark   November 8, 2010 at 6:13PM
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Thanks for the outdoor disconnect suggestion. It looks like I will have to search for one that is not part of the meter box. I already have that part.

For anyone who can help, here is a list of my sketchy notes for requirements on this upgrade.

Two 8' copper ground rods are required. Not sure how far part they should be placed and if distance from the foundation matters...
each clamped to a 8 guage solid copper wire and run to the service panel and also to the meter. Not sure if a specific type of clamp is required. I assume that a clamp like the erico or the tooth type with two screws to tighten it are ok.

I will be installing a mast made from 2" galvanized thick walled pipe( like the kind used for plumbing) that will go through the roof and run along the vinyl siding. It will be attached directly to the meter box using a threaded fitting/hub. ( thread sealed to keep moisture out).

The pipe will go through the typical flashing with a gasket and will be secured to the roof with a guy wire. A metallic weather head will be installed. I will use cowboy straps to fix the mast to the siding. I may also use vinyl siding blocks with plywood underneath to give me a good strong surface for attaching the mast and meter box.

The wire between the service panel through the meter and exposed below the weather head will be 4/0 al or 2/0 cu.

The condiuit below the meter will be routed through a hole in the wall and will go up into the load center. This conduit will be 2" grey PVC with 90 corner with removable plate inside and out to access and run the wire.
I also have a green bonding screw which i believe I must thread through the neutral bus bar to bond it to the service panel.

Thanks again for looking this over !!

    Bookmark   November 8, 2010 at 8:32PM
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Ron Natalie

You (and Smitty) should obtain a copy of the NEC for the version your jurisdiction uses. You'll find it pretty enlightening reading and it has answers to these questions. Also if you inquire with your power company you will also find what specific requirements they may have separate from the code for service location and other requirements.

A 200A outside disconnect will be a good chunk of change and not exactly small. However, if you are a dedicated tinkerer and you figure you may wish to change the inside panel sometime have at it. Frankly, for me, I've only once ever had need to shutoff service to my house (replacing the Zinsco panel) and that was easily done by calling the power co to pull and replace the meter. I've got a 400A disconnect on my current house because the next thing after the meter is the generator transfer switch and you have to be able to disconnect before that.

There's no NEC spacing requirement for grounding rods (other than they need to be at least 6 feet from any electrode for another system, e.g., another structure). Your local authority or power company may have additional requirements again.

You need to use the rod terminal that is listed for the use. Erico makes ones (though I have no idea if you are looking at the right one).

You can not use plumbing pipe as your service mast. I can't imagine of anything that will attach to SIDING that will provide the appropriate support for a service mast. I don't know what "cowboy straps" are but I suspect higly that they're not appropriate either. You will need to attach this into some solid structure. Again, the power company often has specifications for what they want to see in the mast/weatherhead installation.

If you put in the external disconnect switch then you must run FOUR WIRES from the disconnect (two hots, neutral, ground) to the panel. You must remove the bonding screw or whatever your panel has and keep the neutrals and grounds separate in the panel. If you skip the external disconnect, then you can put in the bonding screw and connect things to whatever bar you wish as they will be electrically the same.

    Bookmark   November 9, 2010 at 9:17AM
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Outside disconnects are NOT an NEC requirement, and of limited utility.

    Bookmark   November 9, 2010 at 9:19AM
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Ron Natalie

Oh, and while the wire sizes you stated are legal, you probably can go smaller, it would depend on just which type of conductor you are using.

    Bookmark   November 9, 2010 at 9:19AM
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Distance between ground rods IS specified in the NEC - minimum of 6'... grounding conductor from meter base to ground rods needs to be a minimum 6ga, preferably 4ga copper... mast must be rigid conduit if being used as the attachment point for the service drop... outside disconnect MAY be a local requirement.

IMHO, a service upgrade is not a DIY project, and based on your questions, is beyond the scope of your expertise.

    Bookmark   November 9, 2010 at 3:16PM
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Since others haven't mentioned it I'll say that in case you were thinking along those lines, IMO a main panel replacement isn't a DIY job. I'm a DIY (about 40 years' worth) and though there's not much I hesitate on as long as I study up thoroughly before plunging ahead, I personally wouldn't attempt a main update.

    Bookmark   November 9, 2010 at 3:21PM
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Ron Natalie

Distance between ground rods IS specified in the NEC - minimum of 6'.
Only in the not yet adopted 2011 NEC. There's no specification in earlier ones. The 6' rule applies to electrodes of a DIFFERENT grounding system.

    Bookmark   November 9, 2010 at 8:15PM
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I tackled a service upgrade before I knew what I was doing. Yes, it's more involved than replacing some outlets, but it's still just a matter of knowing what materials to use and what wire goes where.

Looking back at what I've learned since then, most of my errors were in technique, not end result. Everything's in the right place, I just went through a lot more work than necessary to get it there. It also wasn't as neat as my current work.

One major mistake I made was taking the advice of a local hardware store employee even though it sounded wrong to me.

If you ask about everything you are even the tiniest bit unsure of, listen to the advice you receive, and always err on the safe side, the worst that's really going to happen is you're going to spend a week on something that should otherwise be a three-hour project.

    Bookmark   November 9, 2010 at 8:55PM
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", the worst that's really going to happen is you're going to spend a week on something that should otherwise be a three-hour project."

Ummm, a service upgrade like this would take 1 man waaaay more than 3 hours. More like two men, one day. If the OP is planning on having the power back on the same day- he better hire an electrician.

Seriously, way beyond the DIY.

    Bookmark   November 9, 2010 at 9:48PM
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WOW !!. The responses to my post have been fantastic. I really appreciate the time that everyone has spent to help clear some things up.

I know that I should proceed with this upgrade with caution and should understand the entire picture before starting. I also respect the opinions of those who say it should be only attempted by a licensed electrician. I had a similar experience when I ran power to my swimming pool pump. The overall consensus is that bonding pool equipment was too difficult to get right. I was able to review another recent pool install and overall just followed how that was installed. I did have a few pool bonding issues on the deck, but overall it was not too involved.

Getting back to some comments that I read.

I purchased galvanized pipe from an electrical supply company for the mast and realized when i got home that I had a piece of galvanized pipe from a vent in my plumbing that I removed. It was installed when the house was built in 1968. The pipe I bought looked identical to the pipe I had. It was a vent, so other than some rainwater that went in the pipe it was clean... Is there really a difference between these two pipes?

I would like to review the NEC. last time I checked 2005 was the latest. Still the case? I think my town follows the national code to the letter... or at least they did a few years ago. Are there sources for the latest code online?

Thanks for the requirement for the heavier gauge ground wire. 4 gauge it is.

The "cowboy straps" are something that the electrical supply shop sold me. Looks like they are referred to as retaining straps. they go around the galvanized pipe and can be lag bolted to the house on both sides. Looks like these are required every 24". I will probably put some sort of plywood backing behind the siding to be able to bolt these brackets to the house without compressing the siding. I will do the same for the meter box or possibly even use vinyl mounting blocks filled with plywood for the same purpose. I am not sure how this would be done in the field. my current meter was tighted by the siding installers and crushed the siding. I put plywood behind the siding there to fill the voids and that worked out great. Dutch lap siding has those flat sections so it was easy to do.

Thanks again for all the feedback.

    Bookmark   November 9, 2010 at 10:16PM
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I misread the retaining strap requirement was a minimum of two straps at least 24" apart.

I also need to determine from the NEC how high my mast can be. The service connection will be moved from the peak of my single story garage to the side wall.... There is a 4' difference in height between the attachment at the peak and where the mast will pentrate the roof line.

I know there are minimum clearances for structures like the roof ( it will pass over about 3' of roof at that same height ) and there is also a minimum ground clearance that must be satisfied. Based on what I have seen it looks like the power provider mounts to the mast somewhere between 6" and 12" below the top of the weatherhead.

Certainly lots of details to consider.

    Bookmark   November 9, 2010 at 10:33PM
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ontariojer, valid point - I'm not paying much attention - and was just thinking of replacing a meter base, which our local poco seems to think always takes 3 hours. lol

I do agree with you, however - if there needs to be a guarantee of the power being back on in the same day he definitely needs someone who's done it before!

accord500, definitely read the relevant NEC sections, but in addition, contact the power company. They may have additional requirements above and beyond the NEC. Ours (Central Maine Power) has a 'brochure' called "Getting Connected" that consists of several pages of diagrams showing different types of services and what, exactly, they expect - dimensions, clearances, and all.

You may also find when you call them that they expect to (or even simply are willing to) drive out to your location and discuss the location/materials of the new service. I've had this done several times and they've surprised me a couple times with things like "even though this service has been in exactly this spot for the last 35 years, we can't allow you to put the new one here, you need to move it at least ten feet that way and make it higher."

I'm known to be long-winded and am realizing this recently. All I'm really saying is: call the power company and probe THEIR brains for the normal procedure in your area, and local/company-specific requirements.

    Bookmark   November 10, 2010 at 1:07AM
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there is most certainly (and has been as long as i remember) a requirement that the rods be spaced at least 6ft apart. as for the mast, electrical rigid requires that the threads have a 3/4" per foot taper. i may be mistaken about this (i'm not a plumber), but i don't think that your old vent pipe meets this requirement. call your building department about the outside disconnect as different areas have very different rules about this. the 3 counties i work in most often are all different. one doesn't require them at all, one requires only if length of service conductor run inside structure is more than 25ft, and one requires on all installations. and also you have the right wire sizes for the service conductors don't go any smaller as it will not be compliant.

    Bookmark   November 10, 2010 at 2:53AM
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Ron Natalie

Which version of the code depends on what state you are in. 2011 is actually the latest but it is not effective anywhere. 2005 and 2008 are in effect in most places. In 34 states 2008 is the rule, in 6 2005 is the rule, Hawaii still uses 2002. The rest don't have a statewide adoption and it depends on what your local jurisdiction uses.

As pointed out a number of times, for service requirements, there is almost always additional requirements by the power company.

OK pharkus....put up a cite to the NEC where it states a six foot spacing rule for electrodes in the same system? As a matter of fact, show me where it requires two electrodes to be installed to begin with?

    Bookmark   November 10, 2010 at 6:59AM
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The NEC as you probably know does not require that you use electrodes, but if you choose to then I think 250.56 answers both of your questions.

    Bookmark   November 10, 2010 at 7:42AM
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OK pharkus....put up a cite to the NEC where it states a six foot spacing rule for electrodes in the same system? As a matter of fact, show me where it requires two electrodes to be installed to begin with?

If I were the one who said that to begin with, I'd be searching a very large .PDF right now.

    Bookmark   November 10, 2010 at 10:52AM
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From the 2002 NEC Section 250.56: "... Where multiple rod, pipe, plate electrodes are installed to meet the requirements of this section [resistance to ground of 25 ohms or less], they shall not be less than 1.8 m (6 ft) apart."

The wording was changed in 1999, I believe, from the requirement of being 6 ft or more away from any other grounding system.

    Bookmark   November 10, 2010 at 11:45AM
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exact copy from 2008 NEC

"250.56 Resistance of Rod, Pipe, and Plate Electrodes. A
single electrode consisting of a rod, pipe, or plate that does
not have a resistance to ground of 25 ohms or less shall be
augmented by one additional electrode of any of the types
specified by 250.52(A)(4) through (A)(8). Where multiple
rod, pipe, or plate electrodes are installed to meet the requirements
of this"

    Bookmark   November 10, 2010 at 6:52PM
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I really REALLY hate you can't edit your own posts...

copy of the entire article, my above post isn't the entire thing

"250.56 Resistance of Rod, Pipe, and Plate Electrodes. A
single electrode consisting of a rod, pipe, or plate that does
not have a resistance to ground of 25 ohms or less shall be
augmented by one additional electrode of any of the types
specified by 250.52(A)(4) through (A)(8). Where multiple
rod, pipe, or plate electrodes are installed to meet the requirements
of this section, they shall not be less than 1.8 m
(6 ft) apart."

last part, "shall not be less than 6' apart"

    Bookmark   November 10, 2010 at 6:54PM
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Whether the pipes appear identical or not, the proper one probably is labelled as such and approved.

I have to agree with the others, a service upgrade really isn't for a DIYer - the panel inwards is fine if you know what you're doing. You could probably do part or all of the service upgrade yourself, with supervision. Too many variables.

Maybe a friendly electrician will let you be their 'apprentice' and let you do the grunt work that's allowed - digging the ground spikes etc (assuming you can't reuse any of the existing stuff.)

Or at least talk to the relevant authorities for their take on the rules.

    Bookmark   November 11, 2010 at 1:58AM
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I called my local building department and the new electrical inspector asked for detailed plans, which is a good thing. I will work out issues before I "start". Of course I did already do some work... which may have to be undone.

I am also going to have an engineer from the power company show up to review the changes for the service entrance and the mast.

I looked at the NEC 2008 and noticed several red flags even for the things I had done. I installed a conduit to carry the branch circuits from the new main panel and ran a bunch of 12/2 and 14/2 wires from the garage into the house's accessible attic. There I terminated the conduit at an empty panel box.

My problems are that the PVC conduit 2" clearly violates the 40% fill rule ( a 3" might work ), but there was also a restriction for conduit like this that ran long lengths ( about 6' vertical to the unfinished attic in the garage and another 20' into the main house attic. There was writing that suggested it was not ok to have wires "lose" in this conduit going directly into the panel unless it was either for protection or very short lengths. It seemed to suggest that the vertical rise unsupported in the conduit was an issue.

I know one way to change this would be to run the wires up the 2x4s with cable stackers and across the rafters along and stapled to some additional framing added to the rafters. In the attic, all wires could be joined in individual metal boxes rather than a larger empty panel with multiple connections.

I prefer the conduit just for the sake of keeping things looking clean and to give them some protection. The bulk of the house wires run through the center of the attic and are easy to bump when I put things in attic storage.

    Bookmark   November 11, 2010 at 8:47AM
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Aside from ground rods and plumbing pipe, the OP indicated a DIY approach to a service upgrade. My son and I have done a couple hundred service upgrades. It takes the two of us a long day including cutting off power for 5 or 6 hours. Most often it also requires a new service entrance. This is not the type of job that can be drawn out over even a few days.

BTW, we use one 8' copper rod driven in the ground with about 6" showing for connection. That is acceptable with Dallas inspectors. We use 2"schedule 40 pipe for masts. That works best with the weatherheads.

    Bookmark   November 11, 2010 at 10:52AM
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Accord500- Good for you for tackling this yourself! I just had my upgrade done by my electrician - stab lock Federal Pacific Panel now gone, and I am relieved. Service also moved to the front of the house- and will no longer fall off the house in a windstorm! It was too big a job for me to even think about tackling myself!

Anyway- it took my electrician 3+ days to install the new head, service, panel and run new wires to the old panel which now acts as a junction box until I can rewire the whole house. He did all the work by himself- but has been doing this for 20+ years.

For the wires coming into the panel, he ran them into the top of the panel and then made a box out of plywood that covered the wires, but easily removed for work, inspections, etc. Not sure if that works in your state, but is common here. My panel sits in my basement (cripple-wall abve concrete part-panel attached to concrete) and the top is about 18 inches (maybe less) away from the top of the joists. Perhaps that will save your conduit issue?

He had all the right tools too- hammer drill for the old joists, hole saws, etc. Which made things much easier, I'm sure. And I always say, have the right tools for the job.

So, as a DIY'er I am sure you know- what takes the pros only a few days will take the rest of us three times that! Good luck!

    Bookmark   November 11, 2010 at 12:05PM
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A lot of the "don't do this" posts seem to circle around the fact that it *IS* going to take you longer than a professional would to do this.

Who cares?

Assuming the ENTIRE thing is to be replaced, I see this done often in my area (it may be different in the entire rest of the world due to the inspection process, which decidedly lax here): simply install the new service NEXT TO the old one.

Schedule ahead with the power company to come do the switchover. Get all the exterior part up and the new panel in place before that. This'll probably take you an entire day, but you still have power, because the old service is there. Sleep on it. Bright and early on the day when the poco is going to show up, start moving circuits over to the new panel. Start with the important ones you can't live without - such as lighting in the area where the panel is (making sure you still have light to work with until they show up).

Now, in my area, poco will hook up the new service even if you're still moving branch circuits around, just as long as you've got the grounding stuff hooked up and everything up to the main breaker, so if you're not bothered by working inside a live panel (with or without the main turned off, your preference) then it doesn't really matter when they show up.

If it still takes another day, whatever - you got the important stuff moved over first.

I've also temporarily fed the old service (after poco switchover) from the new one...

    Bookmark   November 11, 2010 at 1:02PM
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Pharkus. thanks for the good advice. I will try to make the switchover as painless as possbile. I already have the second panel installed and setup as a subpanel. It is limited to a 40 AMP 220V coming from the first panel. Unfortunately, I will have to undo the wires that I have run from this panel so far.

I definitely want to have the switchover happen in a single day.

Oldhousegal. thanks for the encouragement. I think I understand the plywood channel may remedy the problem with stapling a ton of wires to the sides of 2x4s, and I may also be able to use plastic cable stackers.

texasredhead. Thanks for teh specs on the pipe. I will check at my building dept or online to see if the plumbing pipe is the same thickness.

    Bookmark   November 11, 2010 at 6:32PM
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I never thought about mounting the new panel right next to the old one and just swapping wires which would save a big headache on mine. I had planned on wrecking out the old one and putting the new one in its place which would create a lot more time with no power. I am just doing a panel upgrade from 30 to 40 slots. Sorry Smithy it won't be a QO..and also sorry for hijacking. I just wanted to point out how beneficial it is to plan and plan ahead.

    Bookmark   November 14, 2010 at 11:43PM
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You need to talk with your AHJ and POCO.

In many places the POCO installs masts as required since they are distribution equipment.

The NEC does NOT apply to distribution equipment, the POCO's have their own rules for that (including clearances for wires).

I still occasionally do upgrades in a single 6-8 hour day with just one person and have the power out for less than an hour typically.

By placing the new meter base beside the old one you can use jumpers and shorting strips in the new base to have power back on in a very short time.

As much work is done before disconnecting as possible. New service line from new meter base to new panel location as close to the location of the old panel as possible (this reduces junction boxes to extend the old wiring into the new panel).

Unloaded meters can be pulled (and is is safe) and jumpers installed to power up the new meter base with shorting bars and a feed to the new panel.

Meter back in in less than an 30 minutes, and then a few circuits installed in the new panel (lights and power to work on the panel and refrigerator, freezer, and HVAC circuits right away.

After that it is simply putting the old branch circuits into the new panel.

Having an experienced person guide you through the upgrade is a real help.

Many years ago I worked 4-5 upgrades before the master I worked for allowed me to do them without his immediate supervision the entire time.

It takes a lot of planning to make sure you have everything you need at hand, and the ability to recover from problems that may arise immediately.

Simple things like mounting a new wood panel to the foundation can be problem.
It is best to have a couple methods at your disposal in case there are problems.
Things like multiple spare drills and numerous drill bits for Tapcons.
I can remember a couple old houses with concrete walls so hard you could only get 2-3 holes from a bit.
Having a dozen bits was a good investment.

    Bookmark   November 15, 2010 at 9:58AM
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